John Chrysostom

"And have no confidence," says he, "in the flesh; though I myself might have confidence even in the flesh." What does he call "confidence" here, and "in the flesh"? Boasting, boldness, a high tone. And he did well to add this; for if he had been of the Gentiles, and had condemned circumcision, and not only circumcision, but all those that adopted it out of place, it would have seemed that he was running it down, because he lacked the high ancestry of Judaism, as being a stranger to its solemn rites, and having no part therein. …

Homily on Philippians 10 ↗

Theophylact of Ohrid

If I, he says, came from the Gentiles, then someone might say that I condemn circumcision because I supposedly do not have noble Jewish descent. But now I myself, he says, have the very same thing in which you boast—hope and boasting in fleshly circumcision. So then, it is evident that I condemn circumcision not because I lack, as you say, your nobility, but for the sake of the truth itself. …

Commentary on Philippians ↗

Thomas Aquinas

Then when he says, though I myself have reason for confidence in the flesh also, he gives his own example: first, he mentions the prestige he had under the Law; secondly, he shows how he scorned it (3:7). In regard to the first he does two things: first, he makes a general statement; secondly, he explains it part by part (3:5). …

Commentary on Philippians ↗